The ideal gas law - Safety air bag
Edited BY: Tali Lavy
Edit Date: 2016-08-16 19:44:32

Scientific Background:
The simple gas laws describe the relationships involving the pressure, volume, temperature, and amount of an ideal gas. 
Boyle’s law states that for a fixed amount of gas at a constant temperature, the gas volume is inversely proportional to the gas pressure.  V ∝ (1/P)
Avogadro’s law states that the volume of a gas is proportional to the amount of the gas (at constant temperature and pressure. V ∝ n
Charles law (also called Charles-Gay Lussac’s law) states that the volume of a fixed amount of gas at constant pressure is directly proportional to its temperature (in Kelvin). V ∝ T
The combination of these three laws is: V ∝ (nT)/P
This law can be rearranged to: PV ∝ nT
The proportional relationship can be written as equation: PV=nRT , where R is a proportional constant termed the gas constant.  The value of R (in SI unit) is:  R=8.3145 J mol-1  K-1

Here is a simulation that simulates gas behavior 

Gas Properties

Safety air bags
One well known characteristic of gases in that the expand to fill their containers and assume the shape of their containers.  A practical application of these characteristics is the reaction that forms N2 (g) in an automobile air-bag safety system. This reaction utilizes the rapid decomposition of sodium azide.

2NaN3(s) à Na(l) + 3N2(g)

The essential components of the system are a pellet containing sodium azide and an ignition device. When activated, the system inflates an air bag in a very short time (milliseconds range).  Note: the liquid sodium is converted to harmless solid sodium due to special additives that are also present initially.

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Which statement regarding the above chemical reaction is true:

Question Created By: Tali Lavy
Creation Date: 2016-08-16 18:52:04
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